Aerosol valve for use in high-rate pressure filling of a container

ABSTRACT

An aerosol valve has a housing with a main flow passage at its inner end and an annular seal at its outer end. A valve stem extends through the seal and is movable inwards against a coil spring to open the valve in normal use, and to permit pressure filling by inward deflection of the seal. The internal cross section of the housing over a substantial part of its length is square and flow channels extend from corners of the square through the housing around the outside of the coil spring. Specific characteristics of the seal and spring are stated.

D United States Patent 1151 3,640A36 Gallagher 1 Feb. 8, 1972 [54]AEROSOL VALVE FOR USE IN HIGH- [56] References Cited RATE PRESSURE FHLLING OF A CONTAINER UNITED STATES PATENTS 3,003,662 10/1961 Meshberg..222/402.2 X [721 Imam" Frdemk Jame? Gallagher 89, 381mm 3,160,18212/1964 O'Donnell... ....222/402.l6 x Dflve, "ayes Mlddlesex England3,219,069 11/1965 Kuffer ..222/402.l6 x [22] Filed: Jan. 14, 1970Primary Exammer-Stanley H. Tollberg [21] Appl. No.: 2,716AttameyLawrence E. Laubscher [30] Foreign Application Priority Data [57]ABS CT An aerosol valve has a housing with a main flow passage at itsJan. 17, Griiat Britain inne end and a annular Seal at oute end A v l este ex tends through the seal and is movable inwards against a coil [52]11.8. C1. ..222/402.24 Spring to open the valve i normal use, and topermit pressure [51] Int. Cl ..B65d 83/14 filli by inward d fl ti f thewill. The internal cross [58] Field of Search ..222/402.24, 402.16, 394,402.2, i f th h i over a b ta tial pan of its length is 22 2 square andflow channels extend from comers of the square through the housingaround the outside of the coil spring. Specific characteristics of theseal and spring are stated.

3 Claims, 2 Drawing Figures e w 7 0 J PATENIEU m 8m i 20.436

w I: Gallagher- INVENTOR ATTORNEY AEROSOL VALVE FOR USE IN HIGH-RATEPRESSURE FILLING 01F A CONTAINER This invention relates to aerosolvalves (for pressurized containers) of the type constructed to permitpressure filling of containers on which the valves are mounted.

Such valves usually comprise an annular, elastomeric rubber or syntheticrubber) seal mounted at the outer end of a valve housing, a valve stemslidable through the seal and a coil compression spring within thehousing which urges the stem into sealing engagement with the seal. Thestem is depressed, against the spring, for normal use of the valve, andalso for pressure filling. In the latter case, fluent material underpressure is supplied to the outer surface of the seal, so that the innerperipheral margin thereof deflects inwardly to create an annular flowpassage between the seal and the stem. The pressurized material thenflows through the housing to a main flow passage at the inner end of thehousing, leading to the interior of the container.

There are two main factors affecting the rate at which filling can beeffected. One of these is the available cross-sectional flow area of thehousing, and the other is the area of the flow path which can be createdby deflecting the seal.

As to the first of these factors, the problem facing the designer ofsuch valves is to balance the conflicting requirements between, on theone hand, a large cross section flow path and on the other hand,economic consideration of overall unit cost, and ease of production. Thefirst requirement could easily be met by providing a valve housing ofsubstantial overall size, but this is objectionable because of the spacewhich the valve would then consume in the container, and cost of eachvalve housing, since the major factor in this connection is the weightof material required to make the valve housing. These aerosol valvesare, of course, only manufactured on a mass-production basis, thehousing in particular being formed by injection moulding of syntheticplastic materials, hence the close relationship between weight ofmaterial and cost.

The designer also has to take into account the need to provide adequatelateral support for the coil spring and the expedient most commonlyprovided heretofore is to give the valve housing a generally circularcross section, with inwardly projecting radial vanes which support thecoil spring and define between them flow passages for the material. Amajor disadvantage of this design is that the production of suchhousings by moulding requires the use of a core pin having deep narrowslots along it (to correspond with the radial vanes) and this results inthe core pins being vulnerable to mechanical damage, to an increasedmoulding time (due to the difficult material flow into narrow slots andalso greater care required in stripping the articles from the mouldingtools) and to a fairly high rate of components being rejected because ofimperfections, such as air bubble inclusions in the radial vanes.

The present invention aims at eliminating or reducing some of thesedifiiculties and provides an aerosol valve comprising a valve housinghaving a main flow passage at its inner end, an annular, elastomericseal at the outer end of the housing, and having its outer peripheralmargin sealed to the housing, a central valve stem extending slidablythrough the seal and a coil compression spring contained within thehousing and acting on the valve stem to urge it outwardly into sealingengagement with the seal. The stem being movable inwardly to operate thevalve in normal use and to permit pressure filling by inward deflectionof the inner peripheral margin of the seal, wherein the internal crosssection of the housing over a substantial portion intennediate the innerand outer ends thereof is substantially square, with flow channelsprovided at the corners of the square for the flow of material throughthe housing around the out side of the coil compression spring.

As to the second of the two main factors referred to above, from thepoint of view of facilitating pressure filling, it would obviously beadvantageous to make the seal as pliable as possible to obtain largeseal deflections and a correspondingly large cross section flow path.However, these requirements are in conflict with those for normal use ofa filled container in which the seal is required to close the containeragainst pressure loss for extended periods between intermittentdischarges of small quantities of the material.

In accordance with a further feature of the invention, these conflictingrequirements are carefully balanced by appropriate dimensioning of theseal and selection of the seal material, and in accordance with apreferred feature of the invention, the said seal is from 0.030 inch to0.050 inch thick, its supported diameter is 0.230 inch to 0.270 inch,its internal diameter 0.080 inch to 0.125 inch and is of a rubber orrubberlike material have a Shore hardness of 55-80 IRI-ID.

In accordance with a further preferred feature the spring loading of thevalve in the closed position is from 2 to 5 pounds, with a spring of0.330 inch to 0.430 inch and the stem movement from the closed positionfor pressure filling is 0.050 inch to 0.120 inch.

One form of aerosol valve in accordance with the invention will now bedescribed, by way of example only, with reference to the accompanyingdrawings, in which;

FIG. 1 is a sectional view taken along line l-I of FIG. 2, the left andright hand portions of the valve stem being schematically illustrated inthe closed and open filling positions, respectively; and

FIG. 2 is a section of the housing taken on the line XX of FIG. 1.

The valve shown comprises a valve housing containing a chamber (a) saidhousing being mounted in the usual sheet metal ferrule or mounting cup 2and receiving a central valve stem 3 having a collar 4 normally engagingthe inner surface of a rubber or synthetic rubber valve seal 6 under theaction of a valve spring 7. The ferrule 2 has a central, upstandingflange 8 surrounding the stem 3 with annular clearance, and the ferruleis locally deformed by crimping to form a secure assembly of theferrule, housing and valve seal.

In use, the valve is operated in known manner by depressing the valvestem. Pressure filling is effected, also in known manner, by depressingthe valve stem 3, so that the seal is no longer supported on its innersurface by the collar 4, and supplying material under pressure to theannular clearance between the stem 3 and the flange 8. The material actson the radially inner peripheral margin of the seal, deflecting itinwardly to create a flow path between the seal and the stern for entryof the material into the valve housing I, and so to the interior of thecontainer. The valve housing I contains a valve chamber In having acylindrical upper chamber portion E, an intermediate chamber portion ofsquare cross-sectional configuration, and a cylindrical lower portion Dthat communicates with the inlet 12. The diameters of the upper andlower chamber portions are greater and smaller, respectively, than thespacing distance between opposed pairs of the longitudinally extendingsidewalls a of said intermediate chamber portion. The upper edges of thesidewalls a are connected with the cylindrical wall of the chamber E bythe four diverging walls 17, and the lower edges of the sidewalls a areconnected with the annular transverse bottom wall 14 of the intermediatechamber portion by four converging walls d. The bottom wall 15 of lowerchamber D is counterbored to define a smaller chamber F the bottom wallI6 of which contains the inlet opening 12.

The helical spring 7 that biases the valve stem to the closed positionis seated at its lower end on the bottom wall 14 of the intermediatechamber, the outer diameter of the spring being generally equal to thatof the annular bottom wall 14. The spring is arranged concentricallyabout the valve stem, the upper end of the spring being in engagementwith the collar 4. In order to afford continuous communication betweenvalve chamber portions E and D externally of the spring 7, the housingcontains at each corner of the square intermediate chamber portion alongitudinal channel c that extends from said intermediate chamberportion downwardly beyond said transverse bottom wall 14 toward thelower end of the lower chamber D. This configuration is designed tosecure an adequate cross-sectional area for flow through the housing andpast the spring 7 to cope with the flow rates permitted by the seal 6.

The seal 6 is 0.030 inch to 0.042 inch thick, its supported diameter(i.e., the smallest diameter at which it is supported by the housing) is0.230 inch to 0.270 inch and its internal diameter is 0.080 inch to0.125 inch, and the seal material has a Shore hardness of 55-80 IRHD.

Preferably, the spring loading of the valve in the closed position is2.0 to 5.0 pounds, with a spring length of 0.330 inch to 0.430 inch anda core movement (i.e., spring compression) of 0.050 inch to 0.120 inch.

This combination of dimensions and hardness has been found to give avery good filling rate without reducing the effectiveness of the seal inthe normal conditions of intermittent use of the aerosol valve, withextended periods between uses.

1 claim:

1. Aerosol valve means affording a high charging rate, comprising avalve housing (1) containing a valve chamber (la) and inlet (12) andoutlet openings communicating with the lower and upper ends of saidvalve chamber, said valve chamber including between its upper and lowerends over a substantial part of its length an intermediate portionhaving in transverse cross section a square configuration, saidintermediate chamber portion including four identical longitudinallyextending sidewalls a, four converging walls d connected with the loweredges of said sidewalls, and an annular transverse bottom wall (14)connected with the bottom edges of said converging walls, said bottomwall being counterbored to define a cylindrical lower portion (D) ofsaid valve chamber in communication with said inlet, said housingcontaining at the upper end of said valve chamber an upper cylindricalportion (E) in communication with said outlet, said upper and lowerchambers being colinearly arranged and having diameters that are greaterand smaller, respectively, than the spacing distance between opposedpairs of said sidewalls of said intermediate chamber portion;

annular flexible seal means (6) connected with said housin to close saidoutlet opening, the bore in said seal means being colinear with saidannular bottom wall;

a valve stem (3) slidably mounted in said seal bore for verticalmovement relative to said housing, said valve stem including on itsouter periphery an annular collar (4); and

spring means (7) biasing said valve stem relative to said housing towarda closed position in which said collar is in sealed engagement with saidseal means, said spring means including a helical spring arranged insaid valve chamber concentrically about said valve stem, the lower endof said spring being seated on said transverse bottom wall and the upperend of said spring being in engagement with said collar, the outerdiameters of said helical spring and said annular bottom wall beinggenerally equal; said housing containing at each corner of saidintermediate chamber a longitudinal channel (0) that extends from saidintermediate chamber portion downwardly below said transverse bottomwall in the direction of the lower end of said lower chamber (D),whereby when said inlet opening is connected with a container to becharged and said outlet opening is connected with a source of chargingmaterial, said channels afford a high flow rate of the material fromsaid upper chamber portion to said lower chamber portion externally ofsaid spring means.

2. Aerosol valve means as defined in claim 1, wherein said seal meanshas a thickness of from 0.030 inch to 0.050 inch, a supported diameterof from 0.230 inch to 0.270 inch, and an internal diameter of from 0.080inch to 0.]25 inch, said seal means being formed of a rubberlikematerial having a Shore hardness of from 50 to lRHD.

3. Aerosol valve means as defined in claim 2, wherein said valve stem isspring loaded to the closed position by a loading force of from 2 to 5pounds, wherein said spring has a length of from 0.330 inch to 0.430inch, and wherein the extent of movement of said stem from the closedposition to the pressure filling position is from 0.50 inch to 0.120inch.

1. Aerosol valve means affording a high charging rate, comprising avalve housing (1) containing a valve chamber (1a) and inlet (12) andoutlet openings communicating with the lower and upper ends of saidvalve chamber, said valve chamber including between its upper and lowerends over a substantial part of its length an intermediate portionhaving in transverse cross section a square configuration, saidintermediate chamber portion including four identical longitudinallyextending sidewalls a, four converging walls d connected with the loweredges of said sidewalls, and an annular transverse bottom wall (14)connected with the bottom edges of said converging walls, said bottomwall being counterbored to define a cylindrical lower portion (D) ofsaid valve chamber in communication with said inlet, said housingcontaining at the upper end of said valve chamber an upper cylindricalportion (E) in communication with said outlet, said upper and lowerchambers being colinearly arranged and having diameters that are greaterand smaller, respectively, than the spacing distance between opposedpairs of said sidewalls of said intermediate chamber portion; annularflexible seal means (6) connected with said housing to close said outletopening, the bore in said seal means being colinear with said annularbottom wall; a valve stem (3) slidably mounTed in said seal bore forvertical movement relative to said housing, said valve stem including onits outer periphery an annular collar (4); and spring means (7) biasingsaid valve stem relative to said housing toward a closed position inwhich said collar is in sealed engagement with said seal means, saidspring means including a helical spring arranged in said valve chamberconcentrically about said valve stem, the lower end of said spring beingseated on said transverse bottom wall and the upper end of said springbeing in engagement with said collar, the outer diameters of saidhelical spring and said annular bottom wall being generally equal; saidhousing containing at each corner of said intermediate chamber alongitudinal channel (c) that extends from said intermediate chamberportion downwardly below said transverse bottom wall in the direction ofthe lower end of said lower chamber (D), whereby when said inlet openingis connected with a container to be charged and said outlet opening isconnected with a source of charging material, said channels afford ahigh flow rate of the material from said upper chamber portion to saidlower chamber portion externally of said spring means.
 2. Aerosol valvemeans as defined in claim 1, wherein said seal means has a thickness offrom 0.030 inch to 0.050 inch, a supported diameter of from 0.230 inchto 0.270 inch, and an internal diameter of from 0.080 inch to 0.125inch, said seal means being formed of a rubberlike material having aShore hardness of from 50* to 80* IRHD.
 3. Aerosol valve means asdefined in claim 2, wherein said valve stem is spring loaded to theclosed position by a loading force of from 2 to 5 pounds, wherein saidspring has a length of from 0.330 inch to 0.430 inch, and wherein theextent of movement of said stem from the closed position to the pressurefilling position is from 0.50 inch to 0.120 inch.